import net.egork.utils.Solver;
import net.egork.utils.io.InputReader;

import java.io.PrintWriter;

public class TaskA implements Solver {
    public void solve(int testNumber, InputReader in, PrintWriter out) {

        String s = in.readString();
        int nu = 0, nl = 0;
        for (int i = 0; i < s.length(); ++i)
            if (Character.isLowerCase(s.charAt(i)))
                ++nl;
            else
                ++nu;

        if (nl >= nu)
            out.println(s.toLowerCase());
        else
            out.println(s.toUpperCase());
    }
}
